In a system that monitors apparatuses, an event is periodically executed to collect information of hardware included in the apparatuses to be monitored. The interval of the event is different depending on a type of information to be obtained for the hardware, and there are an event whose execution interval is short and an event whose execution interval is long.
By the way, when the executions of the events concentrate at a specific timing in such a system, there is a case where a load caused by the executions of the events temporarily becomes extremely high. For example, a case is considered that one event whose execution interval is 1 second exists, 10 events whose execution interval is 10 seconds, and 100 events whose execution interval is 100 seconds. In such a case, at a timing when the events whose execution interval is 10 seconds and events whose execution interval is 100 seconds are not executed, only one event whose execution interval is 1 second is executed. However, 11 events are executed every 10 seconds, and 111 events are executed every 100 seconds. Therefore, the number of events executed increases extremely. Thus, when the executions of the events concentrate at a specific timing, a problem occurs that the execution of a portion of the events delays or the like.
Conventionally, as for a system for monitoring apparatuses, a following technique exists. Specifically, when there are a lot of rules, the concentration of collecting the hardware information at a specific timing is avoided by distributing polling in the system over a predetermined period of time. However, because, in this technique, the polling in the system is performed for each rule to collect the hardware information every time, there is a problem that the frequency of the processing becomes high, and the load of the system becomes high.
Patent Document 1: Japanese National Publication of International Patent Application No. 2007-519075
In other words, there is no technique to suppress the increase of the load caused by the executions of the events in case where plural events whose execution intervals are different are executed.